Data converters both analog to digital converters (ADC's) and digital to analog converters (DAC's) often are used in harsh industrial environments such as data acquisition and transfer applications where noise is a serious problem causing errors in the data exchanged between the controller and the data converted. One approach is to reduce the noise to levels where no or very few errors occur using optoisolators, differential signals and hysteresis techniques but these are expensive and space consuming solutions which still can't assure noise free and error free data exchanges. In one technique for detecting errors in the data exchange the data is simply read a second or third time. This severely reduces the data transfer rate or requires faster more expensive systems to maintain the original data transfer rate. Conventional error checking approaches could be used but they require additional and costly error checking logic and/or parity bits which increase the size of the data and processing time. See generally The Ouroboros of the digital consciousness: Linear-feedback-shift registers. EDN Jan. 4, 1996; Digital systems testing and testable design. Pages 431 to 448. ISBN 0-7803-1062-4; and Bebop to the Boolean logic. ISBN 1878707-22-1. Appendix F.